1. Field of the Invention
The present invention relates to a multi-window display apparatus having a multi-window display function, a data telecast receiving apparatus, a multi-window display method, a memory, and a program.
2. Related Background Art
Conventionally, character telecast programming for transmitting character or graphic data multiplexed over normal television broadcasting signals, is implemented as one of broadcasting services in the current analog broadcasting.
Currently available character telecast programs under service include news, weather forecasting, traffic information, travel information, television shopping, and so on. Some programs present questionnaires to viewers during a telecast. This current character telecast programming is done in a method of providing one-way information from a television station to viewers.
However, BS digital broadcasting becoming available at the end of year 2000 in Japan is scheduled to provide the data telecasting with such new services as interactive and on-demand multimedia services added to the character telecasting.
This data telecasting is standardized by Association of Radio Industries and Businesses (ARIB), Japan, and the details of data telecasting are described in the ARIB standard: data telecast encoding and transmission methods in digital broadcasting (ARIB STD B-24). In the standard, the method of presenting the data telecast involves various stipulations to retain “standardized presentation.” The “standardized presentation” means that the same presentation as that intended by a telecast service provider is presented in digital television receivers of all makers, which is strongly recommended.
On the other hand, there are recent television receivers provided with a multi-window display function, e.g., those with a function capable of simultaneously receiving two channels and simultaneously displaying them on a screen.
However, in order for the foregoing digital televisions (digital telecast receiving apparatus) with the multi-window display function to adapt to the presentation of data telecasting, it becomes necessary to modify the window size and layout originally intended by the telecast service provider: for example, it is necessary to convert a window into a scale-down display window.
The reason is nothing but that the data telecast presentation is considered on the basis of display over a full screen. In this case, where a data telecast window consists of a mixture of multimedia information items including characters, graphics, pictures, etc., the discriminability, particularly, of the character information can be heavily degraded with a high possibility.
Methods for avoiding the above problem is described in Japanese Patent Application Laid-Open No. 09-093548 (television receivers with the character information display function). In this application, an imageless region in the screen of the display device is effectively utilized so as to display the character information decoded by a character multiplexing and data telecast decoder, in the imageless region. Furthermore, in the case of a television signal in the letter box method where there appear upper and lower imageless regions, these imageless regions are gathered to either of the upper or lower region and the character information is displayed in the imageless region so as to facilitate recognition and viewing. Making use of the function of presenting display of two windows, there is provided means for enabling display of the character information on either one window. Further, there is another known means of always automatically setting a window for display of character information at a fixed position, as described in Japanese Patent Application Laid-Open No. 09-093505 (a television receiver with a character multiplex decoder). This method can be an effective method for the character telecasting in the current analog broadcasting.
However, when consideration is given to the multi-window display retaining the standardized presentation of data telecast, changing the layout of the character part while ignoring the standardized presentation as in the above avoidance methods, deviates from the intention of the broadcast service provider, and there are thus desires for further improvement.